Symbiotic Relationships & The Circle of Life

A Clark's anemonefish snuggles into the bulbous tentacles of its host anemone. This is an example of a mutualistic symbiosis.
(Ethan Daniels/Shutterstock)

When studying nature, we often focus on predatory relationships.

The falcon captures the pigeon, the lion makes dinner of the zebra, the crocodile attacks the gazelle. We’ve seen these episodes play out thousands of times on nature documentaries, in action movies, and even in our own lives.

But there are other kinds of relationships in nature as well. Some, like the suckerfish and shark, fall under the category of commensalism. The suckerfish attaches to the shark and gets a free ride. The shark is neither helped nor harmed.

And then there's the mother of all relationships: Those built on mutualism, or symbiosis. Consider coral and algae—algae, through photosynthesis, is able to turn carbon dioxide into sugars. The algae makes enough sugar to feed not just itself, but the coral as well. The coral then uses the energy from the sugar to make carbon dioxide for the algae, completing the cycle.

Katie McKissick, also known as “Beatrice the Biologist” online, joins The Takeaway to explain where we see most symbiotic relationships.